.
Thread 4 (Thread 942):
#0  0x00007f5a71d60093 in __poll (fds=<value optimized out>, nfds=<value optimized out>, timeout=<value optimized out>) at ../sysdeps/unix/sysv/linux/poll.c:87
        resultvar = 18446744073709551100
        oldtype = 0
        result = <value optimized out>
#1  0x00007f5a728bfac8 in g_main_context_poll (context=0x98b5e0, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:3474
        poll_func = 0x7f5a728ce070 <g_poll>
#2  g_main_context_iterate (context=0x98b5e0, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:3156
        max_priority = 2147483647
        timeout = -1
        some_ready = <value optimized out>
        nfds = 3
        allocated_nfds = <value optimized out>
        fds = 0x7f5a6c007160
#3  0x00007f5a728c02f2 in g_main_loop_run (loop=0x98b590) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:3369
        __PRETTY_FUNCTION__ = "g_main_loop_run"
#4  0x00007f5a73089516 in gdbus_shared_thread_func (user_data=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./gio/gdbusprivate.c:276
        data = 0x98b5b0
#5  0x00007f5a728e5086 in g_thread_create_proxy (data=0x98b6d0) at /build/buildd/glib2.0-2.29.14/./glib/gthread.c:1962
        thread = 0x98b6d0
        __PRETTY_FUNCTION__ = "g_thread_create_proxy"
#6  0x00007f5a72033d8c in start_thread (arg=0x7f5a6bfff700) at pthread_create.c:304
        pd = 0x7f5a6bfff700
        now = <value optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140026335721216, -370451956288635869, 140026413177696, 140026335721920, 0, 3, 319531373288307747, 319482821271174179}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = 0
        robust = <value optimized out>
        sp = <value optimized out>
        freesize = <value optimized out>
        __PRETTY_FUNCTION__ = "start_thread"
#7  0x00007f5a71d6d1dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
No locals.
#8  0x0000000000000000 in ?? ()
No symbol table info available.
.
Thread 3 (Thread 944):
#0  0x00007f5a7203bcbd in read () at ../sysdeps/unix/syscall-template.S:82
No locals.
#1  0x00007f5a728bb493 in read (data=<value optimized out>) at /usr/include/bits/unistd.h:45
No locals.
#2  unix_signal_helper_thread (data=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:4633
        i = <value optimized out>
        bytes_read = 10008032
        b = "C", '\000' <repeats 126 times>
        sigterm_received = 0
        sigint_received = 0
        sighup_received = 0
#3  0x00007f5a728e5086 in g_thread_create_proxy (data=0x997330) at /build/buildd/glib2.0-2.29.14/./glib/gthread.c:1962
        thread = 0x997330
        __PRETTY_FUNCTION__ = "g_thread_create_proxy"
#4  0x00007f5a72033d8c in start_thread (arg=0x7f5a6afc2700) at pthread_create.c:304
        pd = 0x7f5a6afc2700
        now = <value optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140026318694144, -370451956288635869, 140735459343488, 140026318694848, 0, 3, 319533543857404963, 319482821271174179}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = 0
        robust = <value optimized out>
        sp = <value optimized out>
        freesize = <value optimized out>
        __PRETTY_FUNCTION__ = "start_thread"
#5  0x00007f5a71d6d1dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
No locals.
#6  0x0000000000000000 in ?? ()
No symbol table info available.
.
Thread 2 (Thread 940):
#0  pthread_cond_timedwait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:216
No locals.
#1  0x00007f5a72b734d5 in g_cond_timed_wait_posix_impl (cond=<value optimized out>, entered_mutex=<value optimized out>, abs_time=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./gthread/gthread-posix.c:242
        result = <value optimized out>
        end_time = {tv_sec = 1312205607, tv_nsec = 974866000}
        timed_out = <value optimized out>
        __PRETTY_FUNCTION__ = "g_cond_timed_wait_posix_impl"
#2  0x00007f5a7289414f in g_async_queue_pop_intern_unlocked (queue=0x9820e0, try=0, end_time=0x7f5a709dddb0) at /build/buildd/glib2.0-2.29.14/./glib/gasyncqueue.c:415
        retval = <value optimized out>
        __PRETTY_FUNCTION__ = "g_async_queue_pop_intern_unlocked"
#3  0x00007f5a728949a1 in g_async_queue_timed_pop (queue=0x9820e0, end_time=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gasyncqueue.c:536
        retval = <value optimized out>
        __PRETTY_FUNCTION__ = "g_async_queue_timed_pop"
#4  0x00007f5a728e74c7 in g_thread_pool_wait_for_new_pool (data=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gthreadpool.c:175
        end_time = {tv_sec = 1312205607, tv_usec = 974866}
        pool = <value optimized out>
        local_max_idle_time = 15000
        local_wakeup_thread_serial = <value optimized out>
        local_max_unused_threads = 2
        last_wakeup_thread_serial = 0
        have_relayed_thread_marker = 0
#5  g_thread_pool_thread_proxy (data=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gthreadpool.c:378
        free_pool = <value optimized out>
        task = 0x2
        pool = <value optimized out>
#6  0x00007f5a728e5086 in g_thread_create_proxy (data=0x982650) at /build/buildd/glib2.0-2.29.14/./glib/gthread.c:1962
        thread = 0x982650
        __PRETTY_FUNCTION__ = "g_thread_create_proxy"
#7  0x00007f5a72033d8c in start_thread (arg=0x7f5a709de700) at pthread_create.c:304
        pd = 0x7f5a709de700
        now = <value optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140026413180672, -370451956288635869, 140735459344976, 140026413181376, 0, 3, 319477204623899683, 319482821271174179}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = 0
        robust = <value optimized out>
        sp = <value optimized out>
        freesize = <value optimized out>
        __PRETTY_FUNCTION__ = "start_thread"
#8  0x00007f5a71d6d1dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
No locals.
#9  0x0000000000000000 in ?? ()
No symbol table info available.
.
Thread 1 (Thread 882):
#0  0x0000000000416de1 in xsession_start (session=0x9b29e0) at xsession.c:80
        path = <value optimized out>
        error = 0x0
#1  0x00000000004075db in start_user_session (display=0x9868c0) at display.c:848
        dmrc_file = <value optimized out>
        user = <value optimized out>
        log_filename = 0x9c3010 "\300\071\234"
        result = 0
#2  0x0000000000408d9d in greeter_session_stopped_cb (session=<value optimized out>, display=0x9868c0) at display.c:556
        started_session = <value optimized out>
#3  greeter_session_stopped_cb (session=<value optimized out>, display=0x9868c0) at display.c:532
No locals.
#4  0x00007f5a72d84e94 in g_closure_invoke (closure=0x9b19b0, return_value=0x0, n_param_values=1, param_values=0x9b8fa0, invocation_hint=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./gobject/gclosure.c:773
        marshal = 0x404cc0 <g_cclosure_marshal_VOID__VOID@plt>
        marshal_data = <value optimized out>
        in_marshal = <value optimized out>
        __PRETTY_FUNCTION__ = "g_closure_invoke"
#5  0x00007f5a72d9813b in signal_emit_unlocked_R (node=<value optimized out>, detail=0, instance=0x9b2830, emission_return=0x0, instance_and_params=0x9b8fa0) at /build/buildd/glib2.0-2.29.14/./gobject/gsignal.c:3271
        tmp = <value optimized out>
        handler = 0x998c30
        accumulator = 0x0
        emission = {next = 0x0, instance = 0x9b2830, ihint = {signal_id = 7, detail = 0, run_type = G_SIGNAL_RUN_FIRST}, state = EMISSION_RUN, chain_type = 4}
        class_closure = 0x97b140
        hlist = 0x7f5a72037d70
        handler_list = 0x998c30
        return_accu = 0x0
        accu = {g_type = 0, data = {{v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, v_double = 0, v_pointer = 0x0}, {v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, v_double = 0, v_pointer = 0x0}}}
        signal_id = 7
        max_sequential_handler_number = 28
        return_value_altered = 0
#6  0x00007f5a72da1757 in g_signal_emit_valist (instance=<value optimized out>, signal_id=<value optimized out>, detail=<value optimized out>, var_args=0x7fff870fc258) at /build/buildd/glib2.0-2.29.14/./gobject/gsignal.c:3002
        instance_and_params = 0x9b8fa0
        signal_return_type = 4
        param_values = 0x9b8fb8
        node = 0x976f40
        i = <value optimized out>
        n_params = 0
        __PRETTY_FUNCTION__ = "g_signal_emit_valist"
#7  0x00007f5a72da1922 in g_signal_emit (instance=<value optimized out>, signal_id=<value optimized out>, detail=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./gobject/gsignal.c:3059
        var_args = {{gp_offset = 24, fp_offset = 48, overflow_arg_area = 0x7fff870fc330, reg_save_area = 0x7fff870fc270}}
#8  0x00007f5a728bb2e4 in g_child_watch_dispatch (source=<value optimized out>, callback=<value optimized out>, user_data=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:4534
        child_watch_source = <value optimized out>
        child_watch_callback = <value optimized out>
#9  0x00007f5a728bf5bd in g_main_dispatch (context=0x97bc90) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:2500
        dispatch = 0x7f5a728bb2d0 <g_child_watch_dispatch>
        was_in_call = 0
        user_data = 0x9b2830
        callback = 0x40dcc0 <process_watch_cb>
        cb_funcs = 0x7f5a72b6f650
        cb_data = 0x9b87d0
        current_source_link = {data = 0x9b7180, next = 0x0}
        need_destroy = <value optimized out>
        source = 0x9b7180
        current = 0x96ef60
        i = <value optimized out>
#10 g_main_context_dispatch (context=0x97bc90) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:3083
No locals.
#11 0x00007f5a728bfdb8 in g_main_context_iterate (context=0x97bc90, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:3161
        max_priority = 2147483647
        timeout = -1
        some_ready = 1
        nfds = 3
        allocated_nfds = <value optimized out>
        fds = <value optimized out>
#12 0x00007f5a728c02f2 in g_main_loop_run (loop=0x96d050) at /build/buildd/glib2.0-2.29.14/./glib/gmain.c:3369
        __PRETTY_FUNCTION__ = "g_main_loop_run"
#13 0x0000000000406279 in main (argc=1, argv=0x7fff870fc968) at lightdm.c:921
        pid_file = <value optimized out>
        option_context = <value optimized out>
        explicit_config = 0
        test_mode = 0
        pid_path = 0x418f81 "/var/run/lightdm.pid"
        xserver_command = 0x0
        passwd_path = 0x0
        xsessions_dir = 0x0
        xgreeters_dir = 0x0
        greeter_session = 0x0
        user_session = 0x0
        session_wrapper = 0x0
        config_dir = <value optimized out>
        log_dir = 0x0
        run_dir = 0x0
        cache_dir = 0x0
        default_log_dir = <value optimized out>
        default_run_dir = <value optimized out>
        default_cache_dir = 0x96d050 "\220\274\227"
        minimum_vt = 0x0
        minimum_display_number = 0x0
        show_version = 0
        options = {{long_name = 0x41a150 "config", short_name = 99 'c', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x621898, description = 0x418fcb "Use configuration file", arg_description = 0x0}, {long_name = 0x418fe2 "debug", short_name = 100 'd', flags = 0, arg = G_OPTION_ARG_NONE, arg_data = 0x6218a0, description = 0x418fe8 "Print debugging messages", arg_description = 0x0}, {long_name = 0x419001 "test-mode", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_NONE, arg_data = 0x7fff870fc858, description = 0x418a70 "Run as unprivileged user, skipping things that require root access", arg_description = 0x0}, {long_name = 0x41900b "passwd-file", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc7f8, description = 0x418ab8 "Use the given password file for authentication (for testing, requires --no-root)", arg_description = 0x419017 "FILE"}, {long_name = 0x41901c "pid-file", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc7e8, description = 0x419025 "File to write PID into", arg_description = 0x419017 "FILE"}, {long_name = 0x41903c "xserver-command", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc7f0, description = 0x41904c "Command to run X servers", arg_description = 0x419065 "COMMAND"}, {long_name = 0x4177be "greeter-session", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc810, description = 0x41906d "Greeter session", arg_description = 0x417448 "SESSION"}, {long_name = 0x4177ee "user-session", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc818, description = 0x41907d "User session", arg_description = 0x417448 "SESSION"}, {long_name = 0x417823 "session-wrapper", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc820, description = 0x41908a "Session wrapper", arg_description = 0x417448 "SESSION"}, {long_name = 0x41909a "minimum-vt", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc840, description = 0x418b10 "Minimum VT to use for X servers", arg_description = 0x4190a5 "NUMBER"}, {long_name = 0x4190ac "minimum-display-number", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc848, description = 0x418b30 "Minimum display number to use for X servers", arg_description = 0x4190a5 "NUMBER"}, {long_name = 0x4190c3 "xsessions-dir", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc800, description = 0x418b60 "Directory to load X sessions from", arg_description = 0x4190d1 "DIRECTORY"}, {long_name = 0x4190db "xgreeters-dir", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc808, description = 0x418b88 "Directory to load X greeters from", arg_description = 0x4190d1 "DIRECTORY"}, {long_name = 0x4190e9 "log-dir", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc828, description = 0x4190f1 "Directory to write logs to", arg_description = 0x4190d1 "DIRECTORY"}, {long_name = 0x41910c "run-dir", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc830, description = 0x418bb0 "Directory to store running state", arg_description = 0x4190d1 "DIRECTORY"}, {long_name = 0x419114 "cache-dir", short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_STRING, arg_data = 0x7fff870fc838, description = 0x418bd8 "Directory to cached information", arg_description = 0x4190d1 "DIRECTORY"}, {long_name = 0x41912b "version", short_name = 118 'v', flags = 0, arg = G_OPTION_ARG_NONE, arg_data = 0x7fff870fc85c, description = 0x41911e "Show release version", arg_description = 0x0}, {long_name = 0x0, short_name = 0 '\000', flags = 0, arg = G_OPTION_ARG_NONE, arg_data = 0x0, description = 0x0, arg_description = 0x0}}
        error = 0x0